1. Field of the Invention
The present invention relates to an orthopedic device, and specifically, to an ankle brace for stabilizing an ankle before and after injury. In particular, the ankle brace of the present invention stabilizes the ankle against inversion and eversion and anterior subluxation while allowing normal dorsi-flexion and planter-flexion movement.
2. Background of the Prior Art
After injury to an ankle, such as a fracture or severe ankle sprain, it may be necessary to completely immobilize the ankle through the use of a molded plaster or resin cast. However, once the injury has been stabilized, recovery may be hastened by removing the molded plaster or resin cast and using a removable functional walking brace so that the ankle can be exercised during healing. Also, if the injury is not severe enough to require complete immobilization, it may only be necessary to use a functional walking brace to stabilize the ankle against inversion and eversion while still permitting the normal dorsi-flexion and planter-flexion movement of the ankle.
One such type of walking cast is shown in prior U.S. Pat. No. 4,280,489 listing Glenn W. Johnson Jr. as the inventor. The walking cast shown in the Johnson patent does permit substantially normal dorsi-flexion and planto-flexion movements of the ankle, but limits inversion and eversion to thereby stabilize the ankle. This prior art device is removable and is also adjustable to conform to the ankle.
Unfortunately, the prior art walking brace shown in Johnson U.S. Pat. No. 4,280,489 does not sufficiently immobilize the ankle against inversion and eversion. This is because the prior art Johnson device allows a certain amount of flexture of the brace members in an outward direction so that the ankle may not be sufficiently stabilized against inversion and eversion. In addition, the prior art walking brace shown in the Johnson U.S. Pat. No. 4,280,489 is limited to the use of an air filled bladder or liner to provide a resilient support against the ankle. Such an air filled bladder may also allow for greater movement of the ankle than desired which again would not provide for sufficient stabilization of the ankle against inversion and eversion.